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141.
S. Oikawa T. Kawanishi K. Higuma Y. Matsuo M. Izutsu 《Photonics Technology Letters, IEEE》2003,15(2):221-223
We propose a resonant-type LiNbO/sub 3/ optical modulator with low halfwave voltage. We optimize the phase constant of the electric wave with thick electrodes to reduce the halfwave voltage. The halfwave voltage of the fabricated modulator with 20-/spl mu/m-thick electrodes is 5.8 V at 10.6 GHz. 相似文献
142.
Monolithic fabrication of a new distributed index planar microlens array by means of a deep electromigration technique in a glass substrate is reported. The array consists of distributed index lenses of 1.2 mm in diameter with 6.8 mm focal length. The focused spot is as small as 16 ?m for ?=0.63 ?m. The coupling efficiency of 60% to a multimode VAD fibre has been obtained. 相似文献
143.
The aminoalkoxysilanes, γ-aminopropyltriethoxysilane and N-aminoethyl-γ-ainopropyl-trimethoxysilane, were chemically modified by ring-opening addition of γ-propanesultone. Surfaces coated with polymers from these new monomers have, at the surface, zwitterionic functions of sulfobetaines which are attached to the polymeric siloxane backbone. They showed good wettability, with critical surface tensions as high as 50 dynes/cm. 相似文献
144.
Horimatsu T. Iwama T. Oikawa Y. Touge T. Makiuchi M. Wada O. Nakagami T. 《Lightwave Technology, Journal of》1986,4(6):680-688
Compact transmitter and receiver modules with monolithic optoelectronic-integrated circuits, i.e., OEIC's, are demonstrated, and 400- and 800-Mbit/s transmission experiments are successfully carried out over up to 4 and 2 km, respectively, with these modules, for the first time. The design of the monolithic-integrated circuits and the compact module structure are presented. The soldering technique based on the use of YAG laser simplifies the packaging procedures, and an efficient and simple scheme for coupling between OEIC's and fibers make the OEIC modules compact. Both modules are attractive for applications in high data-rate communication systems, particularly in local area networks, CATV systems, and intra-office links. 相似文献
145.
T Yamamura A Hanai H Oikawa H Matsuzaki K Kikuchi O Akaishi K Seo T Ozasa K Katayama 《Canadian Metallurgical Quarterly》1993,20(11):1516-1519
Fifteen patients with liver metastases from colorectal cancer were treated by arterial infusion of 5-FU and leucovorin. Two regimens were performed. One was weekly bolus infusion of leucovorin following bolus infusion of 5-FU (bolus group), the other was 5 days continuous infusion of 5-FU and leucovorin in 3 weeks (continuous group). One PR was obtained both in the bolus group and in the continuous groups. The objective response rate was 11% in the bolus group and 20% in the continuous group. The one- and 2-year survival rates for these patients were 40% and 0% in the bolus group, and 80% and 60% in the continuous group, respectively. These results suggest that continuous arterial infusion of 5-FU and leucovorin was more effective than individual bolus arterial infusion of leucovorin and 5-FU for patients with liver metastases from colorectal cancer. 相似文献
146.
A 55-year-old woman presented with headache which was characterized by aggravation in the upright position and relief in recumbency. Although intracranial hypotension syndrome was considered to be the most-likely possible entity, computed tomography (CT) scans demonstrated subdural fluid collections associated with findings reminiscent of transtentorial herniation. Because of these CT features, cerebrospinal fluid pressure measurement by a lumbar puncture was not performed. In stead, as an alternative method, she underwent percutaneous subdural tapping, which failed to obtain spontaneous drainage of liquid haematoma, indicating intracranial hypotension. In addition, gadolinium-enhanced magnetic resonance imaging study performed later supported the diagnosis of spontaneous intracranial hypotension. Thus, the usefulness and safety of percutaneous subdural tapping for the diagnosis of spontaneous intracranial hypotension is stressed. 相似文献
147.
Hari Singh Nalwa Atsushi Kakuta Akio Mukoh Hitoshi Kasai Shuji Okada Hidetoshi Oikawa Hachiro Nakanishi Hiro Matsuda 《Advanced materials (Deerfield Beach, Fla.)》1993,5(10):758-760
We have presented a simple technique for the fabrication of nanocrystals of organic molecules and polymers and have shown that it is possible, using the liquid-phase technique, to fabricate organic nanocrystals ranging in size from 10 nm to 1 μm by manipulating the preparative conditions. In particular, nanocrystals of poly(4-BCMU) ranging from 20 nm to 350 nm were prepared by controlling the preparation conditions. The main advantages of the liquid-phase technique are the practicality and suitability of the technique for a wide range of materials. The fabrication of organic nanocrystals, though at a very early stage, seems a promising approach for producing low-dimensional organic materials and, like inorganic nanocrystals, another important objective for future study would be to incorporate organic nanocrystals into a variety of inorganic and organic media. It is hoped that extensive work will be done on organic nanocrystals to evaluate their potential for electronics and photonics. 相似文献
148.
149.
T Yoshioka H Takahashi H Oikawa S Maeda T Ido T Akaizawa H Fukuda R Kanamaru 《Canadian Metallurgical Quarterly》1997,38(5):714-717
This study evaluated the use of PET with 18F-2-deoxy-2-fluoro-D-glucose (18F-FDG) for monitoring chemotherapy effects, using a human cancer xenograft (poorly differentiated human gastric cancer) in vivo model. METHODS: Tumor 18F-FDG uptakes and sizes were measured after administrating mitomycin (MMC), cisplatin (CDDP) and adriamycin (ADR) to xenograft-bearing nude mice and compared with 18F-FDG tumor uptake and tumor size in a non-therapy group. The correlation between the uptake and size was also assessed. RESULTS: The largest reduction in tumor size after chemotherapy occurred in the MMC administered group, followed by the CDDP case, with no reduction in the ADR group as compared to the controls. Fluorine-18-FDG tumor uptake after chemotherapy was also decreased in the MMC and CDDP groups, in that order, but not in the ADR case. With MMC and CDDP, size reduction became significant on Days 8 or 11, whereas 18F-FDG tumor uptake had already been decreased on Days 3 or 7. CONCLUSION: Fluorine-18-FDG uptake decreases in parallel to the efficacy of anticancer agents and correlates with subsequent morphologic changes. We conclude that 18F-FDG PET tumor images are indeed useful for monitoring the effects of cancer chemotherapy. 相似文献
150.